On Sunday morning, NBC aired an interview Mitchell held with Sebelius, just a few days after the secretary resigned after Obamacare topped its first-year enrollment goal.

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There has been speculation that Sebelius' resignation has been in the works since last October, when the Obamacare website, HealthCare.gov, encountered glitches that botched the healthcare plan's rollout, "Morning Joe" host Willie Geist told Mitchell on Monday, asking if she thought that the "writing was on the wall" for the secretary.

Mitchell said she thinks the decision on Sebelius' departure was made more recently than that, but that Sebelius "talked around" her questions about the timing and left a challenge for her successor.

"I think that the decision was made within the last couple of months, that they needed to do something," Mitchell told Geist. "Jeff Zients came in. They did bring in the right tech people to fix the website. They were looking for an exit strategy."

Zients, a former Office of Management and Budget official who became head of the National Economic Council in January, stepped into the fray in October to provide short-term management advice on the project.

He joined a group of experts and specialists drawn from government and industry to diagnose and fix the problems that plagued the rollout.

"I asked her point blank whether she was pushed or jumped and that was her answer," Mitchell told Geist. "She talked around it. Clearly they had been talking about the timing. Once they reached that 7.1 million — and that's only enrollees. We don't know how many are going to pay up. There are a lot of other hurdles to come. Nobody envies [Obama's nominee to replace Sebelius] Sylvia Burwell, if she is easily confirmed as they hope, taking this on."In the interview, Sebelius also admitted the Obama administration's timeline for the new healthcare law's online sign-up system ready to go "was just flat-out wrong," noting that the two months when the healthcare exchange site was plagued with technical problems were "a pretty dismal time" and the low point of her five-year tenure.

But she defended the law's impact and said millions of Americans now have access to healthcare because of it.